The present invention relates to an apparatus and a method for controlling a distance between two traveling vehicles and a recording medium for storing the control method.
To improve the safety in a vehicle driving operation and reduce the driver's burden, an apparatus for automatically controlling a distance between two traveling vehicles is conventionally proposed. For example, a relative speed between the system's vehicle and a preceding vehicle is obtained. A target distance is determined in accordance with the detected relative speed (i.e., speed deviation between two vehicles). An actual distance between the system's vehicle and the preceding vehicle is detected. To eliminate the distance deviation between the actual distance and the target distance, an appropriate target acceleration is set to control an internal combustion engine of the vehicle and/or a braking apparatus so as to realize the target acceleration.
In an automotive vehicle, there are a plurality of deceleration devices which are independently operable to decelerate the vehicle. To adjust the distance between two traveling vehicles, appropriate one or plural deceleration devices are generally selectable in accordance with the target acceleration.
Meanwhile, there is a warning device which generates a warning or alarm to caution the driver against upcoming danger when the distance between two traveling vehicles becomes short. For example, the warning is a buzzer, an indicator or the like, in response to which the driver depresses a braking pedal to give a sufficient braking force to wheels.
However, the warning operation is conventionally independent from the automatic distance control. The condition of the deceleration devices actuated during the automatic distance control is not taken into consideration in the judgement of the warning operation. In some cases, the warning may be issued awkwardly or unexpectedly even if the automatic control apparatus has a sufficient capability of recovering the distance between two vehicles by continuing the automatic distance control. In such cases, the warning operation may not fit to driver's feeling.